In recent years, individual recognition technology which clarifies such as a history of the object by giving an ID (an individual recognition number) to each object; and is useful for production and management of the object has received a lot of attention. For example, there is a technology to be used for production and management, in which information such as a history of the object is clarified by giving an ID (an individual recognition number) to an individual object. Above all, the development of semiconductor devices that can send and receive data without contact has been advanced. As such semiconductor devices, an RFID (Radio Frequency Identification) (also referred to as an ID tag, an IC tag, and IC chip, an RF (Radio Frequency) tag, a wireless tag, an electronic tag, or a wireless chip) and the like are beginning to be introduced into companies, markets, and the like.
Many semiconductor devices such as RFIDs that have already been put to practical use have an element group (also referred to as an IC (Integrated Circuit) chip) and a conductive film functioning as an antenna. These semiconductor devices can exchange data with reader/writer via antenna by an electromagnetic wave.
However, in the case where these semiconductor devices (also referred to as RFID) are mounted on commercial products, a possibility of invading a consumer's privacy is pointed out (Non-Patent Document 1, for example). For example, in the case where an RFID is embedded in a commercial product, there is a possibility that the location of the consumer having the commercial product after purchase is traced. In addition, in the case where an RFID is embedded in a luxury item such as a brand-name product, there is a possibility that information of the RFID is looked at secretly so as to be used for a sort of discrimination of purchasing power. Furthermore, there is a possibility that information of the RFID is rewritten (forged) by a third party. As described above, when an RFID is mounted on a commercial product, the longer the communication range is, the more convenient it is for management and supervision during the distribution process; however, the longer the communication range is, the higher possibility there is that contents of the commercial product is grasped by a third party or the information is forged in the case where the product is purchased by a particular individual.
As a countermeasure for such problems, it can be considered that an RFID is not embedded in a commercial product itself but attached to the price tag or the wrapping paper so as to be removed after purchasing. However, in the case where the tag can be easily removed, there is a fear that the level of security against forgery and theft is lowered. In addition, a measure in which the RFID embedded in a commercial product is destroyed after purchasing so that data is not read externally can be considered. Although this measure is effective when the commercial product is thrown away, information of the commercial product, included in the RFID, cannot be used by the consumer or the producer, and information useful for repair or maintenance of the commercial product will be lost.
[Non-Patent Document] Taiyo Tsuchiya, Privacy of Object, [online], 2004/7, internet (URL: http://www.fri.fujitsu.com/open_knlg/review/rev083/review01.html)